BR122015013886B1 - DEVICE TO DECODE VIDEO - Google Patents

Abstract

device for decoding video. a method and apparatus for encoding video and a method and apparatus for encoding video are provided. the method for decoding video includes: receiving and analyzing an encoded video bit stream; and decoding encoded image data to maximum encoding unit based on information regarding the maximum encoding unit encoded depth, information regarding encoding mode, and encoding unit pattern information.

Description

Technical Field

[0001] Exemplary modalities refer to encoding and decoding video.

Fundamentals of Technique

[0002] As hardware for playing and storing high resolution or high quality video content is being developed and provided, a need for a video codec to effectively encode or decode high resolution or high quality video content is increasing. In a video codec of the related art, the video is encoded according to a limited encoding method based on a macroblock having a predetermined size. Also, in the related art video codec, encoded block pattern information is encoded in macro block units.

Disclosure of InventionTechnical Problem

[0003] Apparatus and methods consistent with exemplary modalities provide video encoding and decoding using information that indicates whether the texture information of an encoding unit has been encoded and in consideration of a hierarchical depth.

Solution of the problem

[0004] According to one aspect of an exemplary embodiment, a method for decoding video is provided, the method including: receiving and analyzing an encoded video bit stream; extract from the bit stream, encoded image data from a current image assigned to a maximum encoding unit of the current image, information about an encoded depth of the maximum encoding unit, information about an encoding mode, and pattern information encoding unit indicating whether the maximum encoding unit texture information has been encoded; and decoding the encoded image data to the maximum encoding unit, based on the information regarding the maximum encoding unit encoded depth, the information regarding the encoding mode, and the encoding unit pattern information.

Advantageous Effects of the Invention

[0005] Encoding unit pattern information based on a hierarchically structured encoding unit and transformation unit is used. Thus, encoding unit pattern information can be encoded in an encoding unit that is larger than a macroblock or is a variously sized data unit. Furthermore, the encoding unit pattern information may be encoded in an encoding unit that includes a plurality of transformation units hierarchically structured according to a tree structure in an integrated manner. Therefore, the efficiency of encoding/decoding and transmitting the encoding unit pattern information can be improved.

Brief Description of Drawings

[0006] The above aspects and/or other aspects will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings in which: FIG. 1 is a block diagram of a video encoding apparatus according to an exemplary embodiment. FIG. 2 is a block diagram of a video decoding apparatus according to an exemplary embodiment. FIG. 3 is a diagram for describing a concept of encoding units according to an exemplary embodiment. FIG. 4 is a block diagram of an image encoder based on encoding units according to an exemplary embodiment. FIG. 5 is a block diagram of an image decoder based on encoding units according to an exemplary embodiment. FIG. 6 is a diagram illustrating deeper encoding units according to depths and partitions according to an exemplary embodiment. FIG. 7 is a diagram for describing a relationship between an encoding unit and transformation units according to an exemplary embodiment. FIG. 8 is a diagram for describing encoding information of encoding units corresponding to an encoded depth in accordance with an exemplary embodiment. FIG. 9 is a diagram of deeper coding units according to an exemplary embodiment. Figs. 10 to 12 are diagrams for describing a relationship between encoding units, prediction units, and transforming units in accordance with an exemplary embodiment. FIG. 13 is a diagram for describing a relationship between an encoding unit, a prediction unit or a partition and a transforming unit according to encoding mode information according to an exemplary embodiment. FIG. 14 is a flowchart illustrating a method for encoding a video according to an exemplary embodiment. FIG. 15 is a flowchart illustrating a method for decoding a video according to an exemplary embodiment. FIG. 16 is a block diagram of a video encoding apparatus using encoding unit pattern information according to an exemplary embodiment. FIG. 17 is a block diagram of a video decoding apparatus using encoding unit pattern information according to an exemplary embodiment. Figs. 18 to 20 are block diagrams illustrating encoding unit pattern information corresponding to an encoded depth when an encoding unit corresponding to an encoded depth includes a transforming unit according to exemplary embodiments. Figs. 21 to 23 illustrate encoding unit pattern information corresponding to an encoded depth when an encoding unit corresponding to the encoded depth includes four transform units in accordance with exemplary embodiments. Figs. 24 to 26 illustrate encoding unit pattern information corresponding to an encoded depth when an encoding unit corresponding to the encoded depth includes a plurality of transform units in accordance with exemplary embodiments. FIG. 27 is a diagram illustrating hierarchical encoding unit pattern information according to an exemplary embodiment. FIG. 28 is a flowchart illustrating a method of encoding video using encoding unit pattern information according to an exemplary embodiment; and FIG. 29 is a flowchart illustrating a method for decoding video using encoding unit pattern information in accordance with an exemplary embodiment.

Best way to carry out the invention

[0007] According to one aspect of an exemplary embodiment, a method for decoding video is provided, the method including: receiving and analyzing an encoded video bit stream; extract from the bit stream, encoded image data from a current image assigned to a maximum encoding unit of the current image, information about an encoded depth of the maximum encoding unit, information about an encoding mode, and pattern information encoding unit indicating whether the maximum encoding unit texture information has been encoded; and decoding the encoded image data to the maximum encoding unit, based on the information regarding the maximum encoding unit encoded depth, the information regarding the encoding mode, and the encoding unit pattern information.

[0008] The encoding unit can be characterized by a maximum size and depth.

[0009] Depth can indicate a number of times an encoding unit is hierarchically divided and as the depth increases, deeper encoding units according to depths can be divided from the maximum encoding unit to obtain encoding units minimums.

[00010] Depth can be deepened from a greater depth to a lesser depth.

[00011] As the depth increases, the number of times the maximum encoding unit is divided may increase, and a possible total number of times the maximum encoding unit is divided may correspond to a maximum depth.

[00012] The maximum size and maximum encoding unit depth can be predetermined.

[00013] Encoding unit pattern information in relation to the maximum encoding unit may include at least one of the encoding unit pattern information corresponding to the encoded depth, which is set to an encoding unit corresponding to the encoded depth, and information coding unit pattern patterns according to transformation depths that indicate whether hierarchical coding unit pattern information with respect to a lower depth has been encoded.

[00014] If the encoding unit pattern information regarding encoding units according to the encoded depths indicates that the texture information of the maximum encoding units has been encoded, decoding the encoded image data may include extracting information from transform unit pattern indicating whether the texture information of at least one transform unit included in the encoding unit corresponding to the encoded depth has been encoded.

[00015] If the transform unit pattern information indicates that the transform unit texture information has been encoded, decoding the encoded image data may include decoding the encoded texture information.

[00016] If the transform unit pattern information indicates that the transform unit texture information was not encoded, decoding the encoded image data may include decoding the transform unit using information about transform units adjacent to the transform unit. processing unit.

[00017] Encoding unit pattern information corresponding to encoded depth can be extracted according to color components of image data.

[00018] If the encoding unit corresponding to the encoded depth includes at least four transform units, the first group can be divided into four lower groups and predetermined bit encoding unit pattern information corresponding to the encoded depth can still be extracted for each of the four lowest groups.

[00019] According to an aspect of another exemplary embodiment, a method for encoding video is provided, the method including: dividing a current image of the video into a maximum encoding unit; determining an encoded depth to produce a final encoding result according to at least one split region which is obtained by splitting a region of the maximum encoding unit according to depths, encoding the at least one splitting region based on a depth which deepens proportionally to a number of times the maximum encoding unit region is divided; and producing image data which is the final encoding result according to the at least one split region and encoding and producing information regarding the encoded depth and a prediction mode and encoding unit pattern information of the maximum encoding unit ; where encoding unit pattern information indicates whether maximum encoding unit texture information has been encoded.

[00020] The output of the image data may include adjusting and encoding the encoding unit pattern information based on whether all the transformation coefficients of the maximum encoding unit texture information are 0.

[00021] The output of the image data may include adjusting and encoding the encoding unit pattern information corresponding to the encoded depth according to the maximum encoding unit encoded depth based on whether all encoding unit transform coefficients corresponding to encoded depths are 0.

[00022] If hierarchical encoding unit pattern information and texture information regarding an encoding unit corresponding to a depth greater than a current depth is not encoded, then the output of the image data may include adjust and encode hierarchical encoding unit pattern information from a depth greater than the current depth.

[00023] The method may further include determining whether at least one of the encoding unit pattern information corresponding to the encoded depth and the hierarchical encoding unit pattern information for each of the at least one transformation depth will be used with respect to at least one of the current image, a slice and the maximum encoding unit.

[00024] The output of the encoding unit pattern information may include determining whether the transform unit pattern information will be adjusted for a transform unit included in an encoding unit corresponding to the encoded depth based on the unit pattern information encoding relative to the maximum encoding unit, where the transform unit pattern information indicates whether the transform unit texture information has been encoded.

[00025] According to an aspect of another exemplary embodiment, an apparatus for decoding video is provided, the apparatus including: a receiver that receives and analyzes an encoded video bit stream; an extractor that extracts from the bit stream, encoded image data from a current image assigned to a maximum encoding unit, information about an encoded depth of the maximum encoding unit, information about an encoding mode, and pattern information encoding unit indicating whether texture information of the maximum encoding unit has been encoded; and an image data decoder that decodes the image data encoded in the maximum encoding unit based on information about the coded depth of the maximum encoding unit, information about the encoding mode, and information about the coding unit pattern information. codification.

[00026] According to an aspect of another exemplary embodiment, an apparatus for encoding video is provided, the apparatus including: a maximum encoding unit splitter which divides a current video image into a maximum encoding unit; a coding unit determiner that determines a coding depth to produce a final coding result according to at least one divided region, which is obtained by dividing a region of each maximum coding unit according to depths encoding the at least one region splitting based on a depth that deepens proportionally to the number of times the maximum encoding unit region is split; and a production unit which generates image data which is the final encoding result according to at least one division region and which encodes and produces encoded depth information and an encoding mode and encoding unit pattern information of the maximum encoding unit, where the encoding unit pattern information indicates whether texture information from each of the at least one maximum encoding unit has been encoded.

[00027] According to an aspect of another exemplary embodiment, a computer readable recording medium is provided having a computer program recorded thereon for performing the above method of video decoding.

[00028] According to an aspect of another exemplary embodiment, a computer readable recording medium is provided having a computer program recorded thereon for performing the above method of video encoding.

[00029] According to an aspect of another exemplary embodiment, a method is provided for decoding video, the method including: extracting from an encoded video bitstream, encoded picture data from a current picture assigned to a maximum encoding unit of the current image, information regarding a maximum encoding unit encoded depth and encoding unit pattern information indicating whether maximum encoding unit texture information has been encoded; and decoding the encoded image data to the maximum encoding unit based on information extracted regarding the maximum encoding unit encoded depth and encoding unit pattern information.

Mode for invention

[00030] In the following, a method and apparatus for encoding video and a method and apparatus for decoding video according to one or more exemplary embodiments will be described with reference to the accompanying drawings. Particularly, video encoding and decoding performed on the basis of encoding units according to a tree structure including spatially independent hierarchical data units according to one or more exemplary embodiments will be described with reference to Figs. 1 to 15. In addition, video encoding and decoding performed using encoding unit pattern information regarding an encoding unit according to such a tree structure in accordance with one or more exemplary embodiments will be described in detail with reference to Figs. 16 to 29. In the present specification, it is understood that expressions such as "at least one of", when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

[00031] In the present specification, an encoding unit is an encoding data unit in which picture data is encoded on an encoding side and an encoded data unit in which encoded picture data is decoded on a decoding side of according to exemplary modalities. Also, an encoded depth indicates a depth where an encoding unit is encoded.

[00032] In the present specification, an "image" can denote a still image for a video or a moving image, that is, the video itself.

[00033] A method and apparatus for encoding video and a method and apparatus for decoding video according to one or more exemplary embodiments will be described with reference to Figs. 1 to 15.

[00034] FIG. 1 is a block diagram of a video encoding apparatus 100 according to an exemplary embodiment. With reference to FIG. 1, the video encoding apparatus 100 includes a maximum encoding unit splitter 110, an encoding unit determiner 120 and an output unit 130.

[00035] Maximum encoding unit splitter 110 can split a current photo based on a maximum encoding unit for the current photo of an image. If the current photo is larger than the maximum encoding unit, the current photo's image data can be divided into at least one maximum encoding unit. The maximum encoding unit according to an exemplary embodiment may be a data unit having a size of 32x32, 64x64, 128x128, 256x256, etc., wherein a shape of the data unit is a square having a width and height in squares. of 2. Image data may be output to encoding unit determiner 120 according to at least one maximum encoding unit.

[00036] An encoding unit according to an exemplary embodiment may be characterized by a maximum size and a depth. Depth denotes a number of times the encoding unit is spatially divided from the maximum encoding unit. Thus, with deepening depth, deeper coding units according to depths can be divided from the maximum coding unit to a minimum coding unit. A maximum encoding unit depth is a higher depth and a minimum encoding unit depth is a lower depth. Since a size of a coding unit corresponding to each depth decreases as the depth of the maximum coding unit deepens, a coding unit corresponding to a greater depth may include a plurality of coding units corresponding to lesser depths.

[00037] As described above, the image data of the current photo is divided into one or more maximum encoding units according to a maximum encoding unit size, and each of the maximum encoding units may include encoding units deeper than are divided according to depth. Since the maximum encoding unit according to an exemplary embodiment is divided according to depths, the image data of a spatial domain included in the maximum encoding unit can be hierarchically classified according to depths.

[00038] The maximum depth and maximum size of an encoding unit that limit the total number of times the height and width of the maximum encoding unit are hierarchically divided can be predetermined.

[00039] Encoding unit determiner 120 encodes at least one divided region obtained by dividing a region of the maximum encoding unit according to depths and determines a depth to output finally encoded image data according to the at least one divided region . For example, encoding unit determiner 120 determines an encoded depth by encoding the image data in the deepest encoding units according to depths according to the maximum encoding unit of the current photo and selecting a depth having at least the minimum of coding errors. Thus, the coding unit encoded image data corresponding to the determined coded depth is output by the coding unit determiner 120. Furthermore, the coding units corresponding to the coded depth can be considered as coding units.

[00040] The coded depth determined and the image data coded according to the coded depth determined are output to the output unit 130.

[00041] The image data in the maximum encoding unit is encoded based on the deepest encoding units corresponding to at least a depth equal to or less than the maximum depth and the results of encoding the image data are compared based on each one of the deeper encoding units. A depth having the least coding errors can be selected after comparing coding errors from the deeper coding units. At least one coding depth can be selected for each maximum coding unit.

[00042] The maximum encoding unit size is divided when an encoding unit is hierarchically divided according to depths and when the number of encoding units increases. Furthermore, even if the encoding units correspond to the same depth in a maximum encoding unit, it is determined whether to divide each of the encoding units corresponding to the same depth to a lower depth by measuring an encoding error of the image data of each encoding unit separately. Thus, even when image data is included in a maximum encoding unit, the image data is divided into regions according to depths, and encoding errors may differ according to the maximum encoding unit. Thus, the encoded depths may differ according to regions in the image data. Therefore, one or more coded depths can be determined in a maximum coding unit and the image data of the maximum coding unit can be divided according to coding units of at least one coded depth.

[00043] Thus, the coding unit determiner 120 can determine coding units having a tree structure included in the maximum coding unit. Encoding units having a tree structure according to an exemplary embodiment include encoding units corresponding to a depth determined to be the encoded depth among all the deepest encoding units included in the maximum encoding unit. An encoding unit of an encoded depth can be hierarchically determined according to depths in the same region as the maximum encoding unit and can be independently determined in different regions. Likewise, a depth encoded in a current region can be determined independently of a depth encoded in another region.

[00044] A maximum depth according to an exemplary embodiment is an index related to a number of times of division from a maximum encoding unit to a minimum encoding unit. A first maximum depth according to an exemplary embodiment may denote a total number of times of division from the maximum encoding unit to the minimum encoding unit. A second maximum depth according to an embodiment of the present invention may denote a total number of levels of depth from maximum encoding unit to minimum encoding unit. For example, when a maximum encoding unit depth is 0, a depth of an encoding unit into which the maximum encoding unit is divided once can be set to 1 and a depth of an encoding unit into which the unit coding unit is divided twice can be set to 2. Here, if the minimum coding unit is an coding unit in which the maximum coding unit is divided four times, 5 depth levels of depths 0, 1, 2, 3 and 4 exist. In this case, the first maximum depth can be set to 4 and the second maximum depth can be set to 5.

[00045] Encoding and prediction transformation can be performed according to the maximum encoding unit. Encoding and predictive transformation can also be performed based on the deepest encoding units according to a depth equal to, or depths less than, the maximum depth according to the maximum encoding unit. The transformation can be performed according to an orthogonal transformation method or an integer transformation.

[00046] Since the number of deeper coding units increases whenever the maximum coding unit is divided according to depths, coding including predictive coding and transformation can be performed on all deeper coding units generated when depth deepens. For convenience of description, the prediction encoding and transformation will now be described on the basis of an encoding unit from a current depth to a maximum encoding unit.

[00047] The video encoding apparatus 100 can variously select a size or format of a data unit for encoding the image data. In order to encode the image data operations such as prediction encoding, transformation and entropy encoding are performed and at this time the same data unit can be used for all operations or different data units can be used for each operation .

[00048] For example, the video encoding apparatus 100 can select not only an encoding unit to encode the image data, but also a data unit other than the encoding unit in order to perform predictive encoding on the image data. in the encoding unit.

[00049] In order to perform prediction coding in the maximum coding unit, prediction coding can be performed based on a coding unit corresponding to a coded depth, i.e. based on a coding unit that is not further divided into encoding units corresponding to a smaller depth. Henceforth, the encoding unit which is no longer divided and becomes a base unit for predictive encoding will be referred to as a prediction unit. A partition obtained by dividing the prediction unit may include a prediction unit or a data unit obtained by dividing at least one of a height and a width of the prediction unit.

[00050] For example, when a 2Nx2N encoding unit (where N is a positive integer) is no longer divided and becomes a 2Nx2N prediction unit, a size of a partition can be 2Nx2N, 2NxN, Nx2N or NxN . Examples of a partition type include symmetric partitions that are obtained by symmetrically dividing a height or width of the prediction unit, partitions obtained by asymmetrically dividing the height or width of the prediction unit (such as l:n or n:l ), partitions that are obtained by geometrically dividing the prediction unit and partitions having arbitrary shapes.

[00051] A prediction mode of the prediction unit can be at least one of an intra mode, an inter mode and a skip mode. For example, intra mode or inter mode can be performed on the partition of 2Nx2N, 2NxN, Nx2N or NxN. Also, skip mode can only be performed on 2Nx2N partition. Coding is performed independently on a prediction unit in a coding unit, thereby selecting a prediction mode having at least one coding error.

[00052] The video encoding apparatus 100 can also perform the transformation of the image data into an encoding unit based not only on the encoding unit for encoding the image data, but also on the basis of a data unit which is different from the encoding unit.

[00053] In order to perform the transformation on the encoding unit, the transformation can be performed on the basis of a data unit having a size less than or equal to the encoding unit. For example, the data unit for the transformation may include a data unit for an intra mode and a data unit for an inter mode.

[00054] A data unit used as a basis for the transformation will be referred to as a transformation unit in the following. The transform depth indicating a number of division times to reach the transform unit by dividing a height and a width of the encoding unit can also be adjusted in the transform unit. For example, in a current encoding unit of 2Nx2N, a transform depth might be 0 when a size of a transform unit is also 2Nx2N, it might be 1 when each of the height and width of the current encoding unit is divided into two equal parts, fully divided into 4A1 transformation units, and the size of the transformation unit is thus NxN, and it can be 2 when each of the height and width of the current encoding unit is divided into four equal parts, fully divided into 4A2 transformation units and the size of the transformation unit is thus N/2xN/2. For example, the transformation unit can be fitted according to a hierarchical tree structure, in which a transformation unit of a higher transformation depth is divided into four transformation units of a lower transformation depth according to hierarchical characteristics of a depth of transformation.

[00055] Similar to the encoding unit, the transform unit in the encoding unit can be recursively divided into smaller sized regions, so that the transform unit can be independently determined in units of regions. Thus, residual data in the encoding unit can be split according to the transformation having the tree structure according to the transformation depths.

[00056] Encoding information according to encoding units corresponding to an encoded depth uses information not only about the encoded depth, but also information about information related to prediction and transformation encoding. Thus, the encoding unit determiner 120 not only determines an encoded depth having a minimum encoding error, but also determines a type of partition in a prediction unit, a prediction mode according to the prediction units, and a size of a processing unit for processing.

[00057] Encoding units according to a tree structure in a maximum encoding unit and a method of determining a partition according to one or more exemplary embodiments will be described in detail later with reference to Figs. 3 to 12.

[00058] The coding unit determiner 120 can measure a coding error of deeper coding units according to depths using Rate Distortion Optimization based on Lagrange multipliers.

[00059] Output unit 130 outputs the maximum encoding unit image data which is encoded based on at least one encoded depth determined by encoding unit determiner 120 and information regarding encoding mode according to the depth encoded in a bit stream. Encoded image data can be obtained by encoding residual data from an image. Information about the encoding mode according to the encoded depth may include at least one of information about the encoded depth, information about the type of partition in the prediction unit, the prediction mode and the size of the transform unit. .

[00060] Information about the encoded depth can be defined using information split according to depths that indicates whether encoding is performed in smaller-depth encoding units rather than an actual depth. If the current depth of the current encoding unit is the encoded depth, image data in the current encoding unit is encoded and output, and thus the split information can be set not to split the current encoding unit to a lesser depth. Alternatively, if the current depth of the current encoding unit is not the encoded depth, encoding is performed in the lowest-depth encoding unit. So the split information can be set to split the current encoding unit to get the lowest depth encoding units.

[00061] If the current depth is not the encoded depth, encoding is performed in the encoding unit which is divided into the encoding unit of the smallest depth. Since at least one smallest depth coding unit exists in a current depth coding unit, coding is performed repeatedly on each smallest depth coding unit. Thus, encoding can be performed recursively for encoding units having the same depth.

[00062] Since encoding units having a tree structure are determined for a maximum encoding unit and information regarding at least one encoding mode is determined for an encoding unit of an encoded depth, the information to respect to at least one encoding mode can be determined for a maximum encoding unit. Furthermore, an encoded depth of the image data of the maximum encoding unit may be different according to locations, since the image data is hierarchically divided according to depths. Thus, information about encoded depth and encoding mode can be adjusted to the image data.

[00063] Thus, the output unit 130 can assign information regarding coding about a corresponding coding depth and coding mode to at least one of the coding unit, the prediction unit and a minimum unit included in the coding unit maximum.

[00064] The minimum unit according to an exemplary embodiment may be a rectangular data unit obtained by dividing the minimum encoding unit having the lowest depth by 4. Alternatively, the minimum unit may be a maximum rectangular data unit which may be included in all encoding units, prediction units, partition units and transformation units included in the maximum encoding unit.

[00065] For example, the coding information output through the output unit 130 can be classified into coding information according to coding units and coding information according to prediction units. The encoding information according to encoding units can include at least one of information about the prediction mode and information about a size of the partitions. The coding information according to the prediction units may include at least one of information about an estimated direction of an inter mode, information about a reference image index of the inter mode, information about a vector of motion, information about a chroma component of an intra mode, and information about an interpolation method of the intra mode. Furthermore, information about a maximum encoding unit size defined according to images, slices or groups of images (GOPs) and information about a maximum depth can be entered into a Sequence Parameter Set (SPS) or a header of a bit stream.

[00066] In the video encoding apparatus 100, the deeper encoding unit may be an encoding unit obtained by dividing at least one of a height and a width of a higher depth encoding unit, which is one layer above, for two. In other words, when the current depth encoding unit size is 2Nx2N, the lowest depth encoding unit size can be NxN. Also, the current depth coding unit having the size of 2Nx2N can include 4 of the lowest depth coding units.

[00067] Thus, the video encoding apparatus 100 can form the encoding units having the tree structure by determining encoding units having an ideal shape and an ideal size for each maximum encoding unit based on the size of the maximum encoding unit and at the maximum depth determined considering characteristics of the current image. Furthermore, since encoding can be performed on each maximum encoding unit using any of several prediction modes and transformations, an optimal encoding mode can be determined by considering encoding unit characteristics of various image sizes.

[00068] Thus, if an image having a high resolution or a large amount of data is encoded in a macroblock of the related technique, the number of macroblocks per image increases excessively. Thus, the number of compressed information generated for each macroblock increases and thus it is difficult to transmit the compressed information and the data compression efficiency decreases. However, using video encoding apparatus 100 according to an exemplary embodiment, image compression efficiency can be increased once an encoding unit is adjusted by considering characteristics of an image while increasing a maximum size of one unit. encoding at the same time considering an image size.

[00069] FIG. 2 is a block diagram of a video decoding apparatus 200 according to an exemplary embodiment. With reference to FIG. 2, video decoding apparatus 200 includes a receiver 210, an image data and encoding information extractor 220, and a picture data decoder 230. Definitions of various terms, such as an encoding unit, a depth, a prediction unit, a transform unit, and information regarding various encoding modes for various operations of the video decoding apparatus 200 are the same or similar to those described above with reference to FIG. 1 and video encoding apparatus 100.

[00070] Receiver 210 receives and analyzes an encoded video bit stream. The encoding and image data information extractor 220 extracts encoded image data for each encoding unit from the analyzed bit stream, wherein the encoding units have a tree structure according to each maximum encoding unit and outputs the data. of image data extracted for the image data decoder 230. The image data information extractor and encoding 220 can extract information regarding a maximum size of an encoding unit of a current image from a header corresponding to the current image or a SPS

[00071] In addition, the image data and encoding information extractor 220 extracts information regarding an encoded depth and an encoding mode for encoding units having a tree structure according to each maximum encoding unit of the stream of bits analyzed. The extracted information about the encoded depth and encoding mode is output to the image data decoder 230. Thus, the image data in a bit stream is divided into the maximum encoding unit, so that the image data decoder image 230 decodes the image data for each maximum encoding unit.

[00072] Information regarding the encoded depth and encoding mode according to the maximum encoding unit can be adjusted to information regarding at least one encoding unit corresponding to the encoded depth. In addition, information about the encoding mode may include at least one of information about a partition type of a corresponding encoding unit corresponding to the encoded depth, information about a prediction mode, and a size of a unit. of transformation. In addition, information divided according to depths can be extracted as the encoded depth information.

[00073] Information regarding the encoded depth and encoding mode according to each maximum encoding unit extracted by the image data and encoding information extractor 220 is information about an encoded depth and an encoding mode determined to generate a minimal coding error when an encoder, such as video coding apparatus 100, repeatedly performs coding for each deeper coding unit according to depths according to each maximum coding unit. Thus, the video decoding apparatus 200 can restore an image by decoding the image data according to an encoded depth and an encoding mode that generates the minimum encoding error.

[00074] Since the information regarding the coded depth and the coding mode can be assigned to a predetermined data unit among a corresponding coding unit, a prediction unit and a minimum unit, the data information extractor from image and encoding 220 can extract the information regarding the encoded depth and encoding mode according to predetermined data units. Predetermined data units to which the same encoded depth and encoding mode information are assigned can be inferred as data units included in the same maximum encoding unit.

[00075] The image data decoder 230 restores the current image by decoding the image data in each maximum encoding unit based on the information regarding the encoded depth and the encoding mode according to the maximum encoding units. In other words, the picture data decoder 230 can decode the encoded picture data based on the information extracted about the partition type, the prediction mode and the transform unit for each encoding unit among the encoding units having the tree structure included in each maximum encoding unit. A decoding process may include at least one of a prediction including intra prediction and motion compensation and an inverse transformation. Inverse transformation can be performed according to the method of inverse orthogonal transformation or inverse integer transformation.

[00076] The picture data decoder 230 can perform intra-prediction or motion compensation according to a partition and a prediction mode of each encoding unit based on the information regarding the partition type and the prediction mode of the encoding unit. coding unit prediction according to coded depths.

[00077] Furthermore, the picture data decoder 230 can perform inverse transformation according to each transform unit in the coding unit based on information regarding the transform unit size of the coding unit according to coded depths, so as to perform the inverse transformation according to the maximum encoding units.

[00078] Image data decoder 230 can determine at least an encoded depth of a current maximum encoding unit using information divided according to depths. If the split information indicates that the image data is no longer split at the current depth, the current depth is an encoded depth. Thus, picture data decoder 230 can decode encoded data of at least one encoding unit corresponding to each encoded depth in the current maximum encoding unit using information regarding the prediction unit's partition type, prediction mode, and the size of the transform unit for each encoding unit corresponding to the encoded depth and send the image data of the current maximum encoding unit.

[00079] In other words, data units including the encoding information including the same divided information can be gathered by looking at the set of encoding information assigned to the predetermined data unit among the encoding unit, prediction unit and unit minimum. Furthermore, the collected data units can be considered as a data unit to be decoded by the picture data decoder 230 in the same encoding mode.

[00080] The video decoding apparatus 200 can obtain information regarding at least one encoding unit that generates the minimum encoding error when encoding is performed recursively for each maximum encoding unit and may use the information to decode the current image. In other words, encoding units having the tree structure determined to be the optimal encoding units in each maximum encoding unit can be decoded. Also, a maximum size of the encoding unit can be determined considering resolution and an amount of image data.

[00081] Thus, even if the image data has a high resolution and a large amount of data, the image data can be efficiently decoded and restored using an encoding unit size and encoding mode that are adaptively determined accordingly. according to characteristics of the image data using information about an optimal encoding mode received from an encoder.

[00082] A method of determining encoding units having a tree structure, a prediction unit and a transform unit, in accordance with one or more exemplary embodiments will now be described with reference to FIGS. 3 to 13.

[00083] FIG. 3 is a diagram for describing a concept of encoding units according to an exemplary embodiment. A size of a coding unit can be expressed in width x height and can be 64x64, 32x32, 16x16 and 8x8, although it is understood that other exemplary embodiments are not limited thereto. A 64x64 encoding unit can be divided into 64x64, 64x32, 32x64 or 32x32 partitions, a 32x32 encoding unit can be divided into 32x32, 32x16, 16x32 or 16x16 partitions, a 16x16 encoding unit can be divided into 16x16, 16x8, 8x16 or 8x8 partitions and an 8x8 encoding unit can be divided into 8x8, 8x4, 4x8 or 4x4 partitions.

[00084] Referring to FIG. 3, first video data 310 has a resolution of 1920x1080, a maximum size of one encoding unit 64 and a maximum depth of 2. Second video data 320 has a resolution of 1920x1080, a maximum size of one encoding unit 64 and a maximum depth of 3. Third video data 330 has a resolution of 352x288, a maximum encoding unit size of 16, and a maximum depth of 1. The maximum depth shown in FIG. 3 denotes a total number of divisions from a maximum encoding unit to a minimum decoding unit.

[00085] If a resolution is high or an amount of data is large, a maximum size of an encoding unit can be large in order to not only increase encoding efficiency, but also accurately reflect features of an image. Thus, the maximum size of the first and second video data encoding units 310 and 320 having a higher resolution than the third video data 330 can be 64.

[00086] Since the maximum depth of the first video data 310 is 2, the encoding units 315 of the first video data 310 may include a maximum encoding unit having a long axis size 64 and encoding units having lengths 32 and 16 long axis, as the depths are deepened to two layers by dividing the maximum encoding unit twice. Meanwhile, since the maximum depth of the third video data 330 is 1, the encoding units 335 of the third video data 330 may include a maximum encoding unit having a long axis size of 16 and the encoding units having a long axis size of 8, since depths are deepened to one layer by dividing the maximum encoding unit once.

[00087] Since the maximum depth of the second video data 320 is 3, the encoding units 325 of the second video data 320 may include a maximum encoding unit having a long axis size of 64 and encoding units having long axis sizes of 32, 16 and 8 as depths are deepened to 3 layers by dividing the maximum encoding unit three times. As depth deepens (ie, increases), detailed information can be accurately expressed.

[00088] FIG. 4 is a block diagram of a picture encoder 400 based on encoding units according to an exemplary embodiment. With reference to FIG. 4, picture encoder 400 performs operations of encoding unit determiner 120 of video encoding apparatus 100 to encode picture data. For example, an intra predictor 410 performs intra prediction in coding units in an intra mode, between a current frame 405 and a motion estimator 420 and a motion compensator 425 performs inter estimation and motion compensation, respectively, in coding units. in an inter mode within the current frame 405 using the current frame 405 and a reference image 495.

[00089] Data output from intrapredictor 410, motion estimator 420 and motion compensator 425 is sent as a quantized transform coefficient through a transformer 430 and a quantizer 440. The quantized transform coefficient is restored as data in a domain through an inverse quantizer 460 and an inverse transformer 470. The restored data in the spatial domain is output as the reference frame 495 after being post-processed through an unlocking unit 480 and an in-circuit filtering unit 490 The quantized transform coefficient may be output as a bit stream 455 through an entropy encoder 450.

[00090] In order for the picture encoder 400 to be applied to the video encoding apparatus 100, elements of the picture encoder 400, i.e. the intra predictor 410, the motion estimator 420, the motion compensator 425, the transformer 430, quantizer 440, entropy encoder 450, inverse quantizer 460, inverse transformer 470, unlocking unit 480, and in-loop filtering unit 490 perform operations based on each encoding unit among the coding units. encoding having a tree structure while considering the maximum depth of each maximum encoding unit.

[00091] Specifically, the intra predictor 410, the motion estimator 420 and the motion compensator 425 determine partitions and a prediction mode of each encoding unit among encoding units having a tree structure, while considering a maximum size and a maximum depth of a current maximum coding unit, and transformer 430 determines a transform unit size in each coding unit among the coding units having a tree structure.

[00092] FIG. 5 is a block diagram of a picture decoder 500 based on encoding units according to an exemplary embodiment. With reference to FIG. 5, an analyzer 510 analyzes encoded image data to be decoded and information regarding the encoding used to decode from a bit stream 505. The encoded image data is sent as inverse quantized data through an entropy decoder 520 and a quantizer. inverse 530, and the inverse quantized data is restored to image data in a spatial domain through an inverse transformer 540.

[00093] An intra predictor 550 performs intra prediction on encoding units in an intra mode with respect to image data in the spatial domain and a motion compensator 560 performs motion compensation on encoding units in an inter mode using a reference frame 585.

[00094] Spatial domain image data passed through intrapredictor 550 and motion compensator 560 may be sent as a restored frame 595 after being post-processed through unlocking unit 570 and in-circuit filtering unit 580 In addition, the image data that is post-processed through the unlocking unit 570 and the in-circuit filtering unit 580 can be sent as the reference frame 585.

[00095] In order to decode the picture data in the picture data decoder 230 of the video decoding apparatus 200, the picture decoder 500 can perform operations that are performed after the analyzer 510.

[00096] In order for the picture decoder 500 to be applied to the video decoding apparatus 200, elements of the picture decoder 500, i.e. the analyzer 510, the entropy decoder 520, the inverse quantizer 530, the inverse transformer 540, intrapredictor 550, motion compensator 560, unlocking unit 570, and in-circuit filtering unit 580 perform operations based on encoding units having a tree structure for each maximum encoding unit.

[00097] Specifically, intra prediction 550 and motion compensator 560 perform operations based on partitions and a prediction mode for each of the encoding units having a tree structure and inverse transformer 540 perform operations based on a size of one transformation unit for each encoding unit.

[00098] FIG. 6 is a diagram illustrating deeper encoding units according to depths and partitions according to an exemplary embodiment. A video encoding apparatus 100, according to an exemplary embodiment, and a video decoding apparatus 200, according to an exemplary embodiment, use hierarchical encoding units in order to account for features of an image. A maximum height, maximum width and maximum depth of encoding units can be adaptively determined according to the image characteristics, or can be differently adjusted by a user. Deeper encoding unit sizes according to depths can be determined according to a predetermined maximum encoding unit size.

[00099] Referring to FIG. 6, in a hierarchical structure 600 of encoding units according to an exemplary embodiment, the maximum height and maximum width of the encoding units are each 64 and the maximum depth is 4. that is, increases) along a vertical axis of the hierarchical structure 600, a height and a width of the deepest encoding units are each divided. In addition, a prediction unit and divisions, which are bases for predicting encoding of each deeper encoding unit, are shown along a horizontal axis of the hierarchical structure 600.

[000100] For example, a first encoding unit 610 is a maximum encoding unit in the hierarchical structure 600, where a depth thereof is 0 and a size, i.e. height per width, thereof is 64x64. The depth deepens along the vertical axis such that the hierarchical structure 600 includes a second encoding unit 620 having a size of 32x32 and a depth of 1, a third encoding unit 630 having a size of 16x16 and a depth of 2 , a fourth encoding unit 640 having a size of 8x8 and a depth of 3, and a fifth encoding unit 650 having a size of 4x4 and a depth of 4. The fifth encoding unit 650 having a size of 4x4 and the depth of 4 is a minimum encoding unit.

[000101] The prediction unit and the partitions of the encoding units 610, 620, 630, 640 and 650 are arranged along the horizontal axis according to each depth. In other words, if the first encoding unit 610 having a size of 64x64 and a depth of 0 is a prediction unit, the prediction unit can be divided into partitions included in the first encoding unit 610, i.e. a partition 610 having a size of 64x64, partitions 612 having a size of 64x32, partitions 614 having a size of 32x64, or partitions 616 having a size of 32x32.

[000102] Likewise, a prediction unit of the second encoding unit 620 having a size of 32x32 and a depth of 1 can be divided into partitions included in the second encoding unit 620, that is, a partition 620 having a size of 32x32, partitions 622 having a size of 32x16, partitions 624 having a size of 16x32, and partitions 626 having a size of 16x16.

[000103] Likewise, a prediction unit of the third encoding unit 630 having a size of 16x16 and a depth of 2 can be divided into partitions included in the third encoding unit 630, i.e. a partition having a size of 16x16 included in the third encoding unit 630, partitions 632 having a size of 16x8, partitions 634 having a size of 8x16 and partitions 636 having a size of 8x8.

[000104] Likewise, a prediction unit of the fourth encoding unit 640 having a size of 8x8 and a depth of 3 can be divided into partitions included in the fourth encoding unit 640, i.e. a partition having a size of 8x8 included in the fourth encoding unit 640, partitions 642 having a size of 8x4, partitions 644 having a size of 4x8 and partitions 646 having a size of 4x4.

[000105] The fifth coding unit 650 having a size of 4x4 and a depth of 4 is the minimum coding unit and a coding unit of the lowest depth. A prediction unit of the fifth encoding unit 650 is assigned to a partition having a size of 4x4.

[000106] In order to determine the at least one coded depth of the encoding units of the maximum decoding unit 610, the decoding unit determiner 120 of the video encoding apparatus 100 performs encoding for encoding units corresponding to each depth included in the encoding unit. maximum encoding 610.

[000107] Numerous encoding units deeper according to depths including data in the same range and in the same size increase as the depth deepens. For example, four encoding units corresponding to a depth of 2 are needed to cover data that are included in one encoding unit corresponding to a depth of 1. Consequently, in order to compare encoding results of the same data according to depths, the encoding unit corresponding to the depth of 1 and four encoding units corresponding to the depth of 2 are each encoded.

[000108] In order to perform coding for a current depth between depths, a minimum coding error can be selected for the current depth by performing coding for each prediction unit in the coding units corresponding to the current depth along the horizontal axis of the hierarchical structure 600. Alternatively, the minimum coding error may be sought by comparing the minimum coding errors according to depths, by performing coding for each depth as the depth deepens along the vertical axis of the hierarchical structure 600 A depth and a partition having the least encoding error in the first encoding unit 610 can be selected as the encoded depth and a partition type of the first encoding unit 610.

[000109] FIG. 7 is a diagram for describing a relationship between an encoding unit 710 and transforming units 720 according to an exemplary embodiment. A video encoding apparatus 100 according to an exemplary embodiment and a video decoding apparatus 200 according to an exemplary embodiment respectively encode and decode a picture according to encoding units having sizes less than or equal to one unit of maximum encoding for each maximum encoding unit. Transform unit sizes for transformation during encoding can be selected based on data units that are not larger than a corresponding encoding unit.

[000110] Referring to FIG. 7, for example, in video encoding apparatus 100, if a size of encoding unit 710 is 64x64, transformation can be performed using transforming units 720 having a size of 32x32.

[000111] In addition, data from encoding unit 710 having the size of 64x64 can be encoded by performing the transformation on each of the transforming units having the size of 32x32, 16x16, 8x8 and 4x4, which are smaller than 64x64, and in then a transform unit having the least coding errors can be selected.

[000112] FIG. 8 is a diagram for describing encoding information of encoding units corresponding to an encoded depth in accordance with an exemplary embodiment. With reference to FIG. 8, the output unit 130 of a video encoding apparatus 100 according to an exemplary embodiment can encode and transmit first information 800 about a partition type, second information 810 about a prediction mode, and third information 820 about a size of a transformation unit for each encoding unit corresponding to an encoded depth, as information about an encoding mode.

[000113] The first information 800 indicates information about a shape of a partition obtained by dividing a prediction unit from a current encoding unit, where the partition is a data unit for encoding prediction encoding from the current encoding unit. For example, a current encoding unit CU_O having a size of 2Nx2N can be split into any one of an 802 partition having a size of 2Nx2N, an 804 partition having a size of 2NxN, an 806 partition having a size of Nx2N and a partition 808 having a size of NxN. Here, the first information 800 about a partition type is set to indicate one of partition 804 having a size of 2NxN, partition 806 having a size of Nx2N, and partition 808 having a size of NxN.

[000114] The second information 810 indicates a prediction mode for each partition. For example, the second information 810 may indicate a predictive encoding mode performed on a partition indicated by the first information 800, i.e., an intra mode 812, an inter mode 814, or a skip mode 816.

[000115] The third information 820 indicates a transformation unit to be based on when the transformation is performed on a current encoding unit. For example, the transform unit can be a first intra transform unit 822, a second intra transform unit 824, a first inter transform unit 826 or a second intra transform unit 828.

[000116] An image data information extractor and encoding 220 of a video decoding apparatus 200 according to an exemplary embodiment can extract and use information 800, 810 and 820 for decoding according to each deeper encoding unit .

[000117] FIG. 9 is a diagram of deeper encoding units according to depths, according to an exemplary embodiment. Split information can be used to indicate a change in depth. Split information indicates whether an encoding unit of a current depth is split into encoding units of a lower depth.

[000118] Referring to FIG. 9, a prediction unit 910 for encoding prediction of an encoding unit 900 having a depth of 0 and a size of 2N_0x2N_0 may include partitions of a partition type 912 having a size of 2N_0x2N_0, a partition type 914 having a size of 2N_0xN_0, a partition type 916 having a size of N_0x2N_0 and a partition type 918 having a size of N_0xN_0. FIG. 9 only illustrates the partition types 912 to 918 that are obtained by symmetrically dividing the prediction unit 910, but it is understood that a partition type is not limited thereto in another exemplary embodiment. For example, according to another exemplary embodiment, the partitions of the prediction unit 910 may include asymmetric partitions, partitions having a predetermined shape, and partitions having a geometric shape.

[000119] Predictive coding is performed repeatedly on one partition having a size of 2N_0x2N_0, two partitions having a size of 2N_0xN_0, two partitions having a size of N_0x2N_0, and four partitions having a size of N_0xN_0 according to each partition type. Predictive coding in an intra mode and an inter mode can be performed on partitions having sizes of 2N_0x2N_0, N_0x2N_0, 2N_0xN_0 and N_0xN_0. Predictive encoding in a skip mode is performed only on the partition having the size of 2N_0x2N_0.

[000120] Encoding errors including prediction encoding in partition types 912 to 918 are compared and the minimum encoding error is determined between partition types. If a coding error is minor in one of partition types 912 to 916, the prediction unit 910 cannot be split to a lower depth.

[000121] If the coding error is the smallest in partition type 918, a depth is changed from 0 to 1 to divide partition type 918 in operation 920 and coding is repeatedly performed in coding units 930 having a depth of 2 and a size of N_0xN_0 to look for a minimum encoding error.

[000122] The prediction unit 940 for encoding prediction of the encoding unit 930 having a depth of 1 and a size of 2N_lx2N_l (=N_0xN_0) may include partitions of a partition type 942 having a size of 2N_lx2N_l, a partition type 944 having a size of 2N_lxN_l, a partition type 946 having a size of N_lx2N_l, and a partition type 948 having a size of N_lxN_l.

[000123] If an encoding error is the smallest in partition type 948, a depth is changed from 1 to 2 to divide partition type 948 in operation 950, and encoding is repeatedly performed in encoding units 960 that have a depth of 2 and a size of N_2xN_2 to look for a minimum encoding error.

[000124] When a maximum depth is d, division operations according to each depth can be performed until when a depth becomes d-1, and divided information can be encoded even when a depth is one from 0 to d-2. For example, when coding is done up to when the depth is d-1 after a coding unit corresponding to a depth of d-2 is divided in operation 970, a prediction unit 990 for predictive coding of a coding unit 980 having a depth of d-1 and a size of 2N_(d-1)x2N_(d-1) may include partitions of a partition type 992 having a size of 2N_(d-1)x2N_(d-1), a partition type 994 having a size of 2N_(d-1)xN_(d-1) , a partition type 996 having a size of N_(d-1)x2N_(d-1) and a partition type 998 having a size of N_(d-1)xN_(d-1) .

[000125] Predictive coding can be performed repeatedly on one partition having a size of 2N_(d-l)x2N_(dl), two partitions having a size of 2N_(d-1)xN_(d-1), two partitions having a size of N_(d-1)x2N_(d-1), four partitions having a size of N_(d-1)xN_(d-1) between partition types 992 to 998 to look for a partition type having a minimum encoding error.

[000126] Even when partition type 998 has the minimum encoding error, since the maximum depth is d, an encoding unit CU_(dl) having a depth of d-1 is no longer split into a lower depth and a coded depth for the encoding units of a current maximum encoding unit 900 is determined to be d-1 and a partition type of the current maximum encoding unit 900 can be determined to be N_(d-1)xN_(d - 1) . Also, since the maximum depth is d and a minimum encoding unit 980 having a lower depth of d-1 is no longer split into a smaller depth, split information for the minimum encoding unit 980 is not established.

[000127] A data unit 999 can be considered a minimum unit for the current maximum encoding unit. A minimum unit according to an exemplary embodiment may be a rectangular data unit obtained by dividing a minimum encoding unit 980 by 4. By performing encoding repeatedly, a video encoding apparatus 100 according to an exemplary embodiment may select a depth having the minimum coding error by comparing coding errors according to coding unit depths 900 to determine an coded depth and defining a corresponding partition type and prediction mode as a coding depth coding mode.

[000128] As such, the minimum encoding errors according to depths are compared across all depths from 1 to d and a depth having the minimum encoding errors can be determined as an encoded depth. At least one of the encoded depth, the prediction unit partition type, and the prediction mode may be encoded and transmitted as information about an encoding mode. Also, since an encoding unit is divided from a depth of 0 to an encoded depth, only information divided from the encoded depth is set to 0 and information divided from depths excluding the encoded depth is set to 1.

[000129] An image data information extractor and encoding 220 of a video decoding apparatus 200 according to an exemplary embodiment can extract and use the encoded depth information from the prediction unit of the encoding unit 900 to decode the partition 912. The video decoding apparatus 200 can determine a depth at which the divided information is 0 as an encoded depth using information divided according to depths and use information regarding a corresponding depth encoding mode for decoding.

[000130] FIGS. 10 to 12 are diagrams for describing a relationship between encoding units 1010, prediction units 1060 and transforming units 1070 according to an exemplary embodiment.

[000131] Referring to FIGS. 10 to 12, encoding units 1010 are encoding units having a tree structure corresponding to encoded depths determined by a video encoding apparatus 100 according to an exemplary embodiment in a maximum encoding unit. The prediction units 1060 are partitions of prediction units of each of the decoding units 1010 and the transforming units 1070 are transforming units of each of the encoding units 1010.

[000132] When a maximum encoding unit depth is 0 in encoding units 1010, encoding units depths 1012 and 1054 are 1, encoding units depths 1014, 1016, 1018, 1028, 1050 and 1052 are of 2, encoding unit depths 1020, 1022, 1024, 1026, 1030, 1032, and 1048 are 3, and encoding unit depths 1040, 1042, 1044, and 1046 are 4.

[000133] In the prediction units 1060, some encoding units 1014, 1016, 1022, 1032, 1048, 1050, 1052 and 1054 are obtained by dividing the encoding units from the encoding units 1010. For example, partition types in the Encoding units 1014, 1022, 1050 and 1054 have a size of 2NxN, partition types in encoding units 1016, 1048 and 1052 have a size of Nx2N, and a partition type of encoding unit 1032 has a size of NxN. Predictive units and partitions of encoding units 1010 are less than or equal to each encoding unit.

[000134] Transformation or inverse transformation is performed on image data from encoding unit 1052 to transforming units 1070 into a data unit that is smaller than encoding unit 1052. Further, encoding units 1014, 1016, 1022, 1032, 1048, 1050 and 1052 in transforming units 1070 are different from those in predicting units 1060 in terms of sizes and shapes. For example, video encoding and decoding apparatus 100 and 200 according to exemplary embodiments can perform intra prediction, motion estimation, motion compensation, transformation and inverse transformation individually on a data unit in the same encoding unit.

[000135] Therefore, coding is performed recursively on each of the coding units having a hierarchical structure in each region of a maximum coding unit to determine an optimal coding unit and thus coding units having a tree structure recursive can be obtained. Encoding information can include at least one of divided information about an encoding unit, information about a partition type, information about a prediction mode, and information about a size of a transformation unit. Table 1 shows exemplary encoding information that can be set by video encoding and decoding apparatus 100 and 200.

[000136] An output unit 130 of the video encoding apparatus 100 can send encoding information regarding encoding units having a tree structure and an image data information extractor and encoding 220 of the video decoding apparatus 200 can extract encoding information regarding encoding units having a tree structure from a received bit stream.

[000137] Split information indicates whether a current encoding unit is divided into lower depth encoding units. If the split information from a current depth is 0, the depth at which a current encoding unit is no longer split into a lower depth is an encoded depth, and thus information regarding a partition type, prediction mode and a size of one transform unit can be set to the encoded depth. If the current encoding unit is further divided according to the divided information, encoding is performed independently in four divided encoding units of a lower depth.

[000138] A prediction mode can be one of an intra mode, an inter mode and a skip mode. Intra mode and inter mode can be set on all partition types and skip mode can be set only on one partition type having a size of 2Nx2N.

[000139] Information regarding partition type may indicate symmetric partition types having sizes of 2Nx2N, 2NxN, Nx2N and NxN which are obtained by symmetrically dividing at least one of a height and a width of a prediction unit and partition types asymmetrical having sizes of 2NxnU, 2NxnD, nLx2N and nRx2N which are obtained by asymmetric division of at least one of the height and width of the prediction unit. Asymmetric partition types having sizes of 2NxnU and 2NxnD can be obtained, respectively, by dividing the prediction unit height into 1:3 and 3:1, and asymmetric partition types having sizes of nLx2N and nRx2N can be obtained, respectively, dividing the prediction unit width into 1:3 and 3:1

[000140] The size of the transformation unit can be set to be two types in intra mode and two types in inter mode. For example, if the split transform unit information is 0, the transform unit size can be 2Nx2N which is the current encoding unit size. If the divided transform unit information is 1, the transform units can be obtained by dividing the current encoding unit. Also, if a partition type of the current encoding unit having the size of 2Nx2N is a symmetric partition type, a size of a transform unit can be NxN and if the partition type of the current encoding unit is a type of asymmetric partition, the size of the transformation unit can be N/2xN/2.

[000141] Encoding information regarding encoding units having a tree structure may include at least one of an encoding unit corresponding to an encoded depth, a prediction unit and a minimum unit. The encoding unit corresponding to the encoded depth may include at least one of a prediction unit and a minimum unit including the same encoding information.

[000142] Therefore, it is determined whether adjacent data units are included in the same encoding unit corresponding to the encoded depth by comparing the encoding information of the adjacent data units. Furthermore, a corresponding encoding unit corresponding to an encoded depth is determined using encoding information from a data unit, and therefore a distribution of encoded depths in a maximum encoding unit can be determined.

[000143] Therefore, if a current encoding unit is predicted based on encoding information from adjacent data units, encoding information from data units in deeper encoding units adjacent to the current encoding unit can be directly queried and used .

[000144] Alternatively, if a current encoding unit is predicted based on encoding information from adjacent data units, data units adjacent to the current encoding unit are searched using the encoding information from the data units and encoding units adjacent queries can be queried to predict the current encoding unit.

[000145] FIG. 13 is a diagram for describing a relationship between an encoding unit, a prediction unit or a partition and a transforming unit, in accordance with the encoding mode information of Table 1 according to an exemplary embodiment. With reference to FIG. 13, a maximum encoding unit 1300 includes encoding units 1302, 1304, 1306, 1312, 1314, 1316, and 1318 and encoded depths. Here, since encoding unit 1318 is an encoding unit of an encoded depth, the divided information can be set to 0. Information regarding a partition type of encoding unit 1318 having a size of 2Nx2N can be set to be one of a partition type 1322 having a size of 2Nx2N, a partition type 1324 having a size of 2NxN, a partition type 1326 having a size of Nx2N, a partition type 1328 having a size of NxN, a partition type partition 1332 having a size of 2NxnU, a partition type 1334 having a size of 2NxnD, a partition type 1336 having a size of nLx2N, and a partition type 1338 having a size of nRx2N.

[000146] When the partition type is set to be symmetric, i.e. partition type 1322, 1324, 1326 or 1328, a transform unit 1342 having a size of 2Nx2N is set if the split information (TU size flag ) of a transform unit are 0, and a transform unit 1344 having a size of NxN is set if a TU size flag is 1.

[000147] When the partition type is set to be asymmetric, i.e. partition type 1332, 1334, 1336 or 1338, a transform unit 1352 having a size of 2Nx2N is set if a TU size flag is 0 and a transform unit 1354 having a size of N/2xN/2 is set if a TU size flag is 1.

[000148] Referring to FIG. 13, the TU size flag is a flag having a value of 0 or 1, although it is understood that another exemplary embodiment is not limited to a 1-bit flag. For example, a transformation unit can be hierarchically split having a tree structure while the TU size flag increases from 0 in the other exemplary embodiment.

[000149] In this case, the size of a transformation unit that was actually used can be expressed using a TU size flag of a transformation unit according to an exemplary modality, together with a maximum size and minimum size of the transformation unit . According to an exemplary embodiment, a video encoding apparatus 100 can encode maximum transform unit size information, minimum transform unit size information and maximum TU size flag. The encoding result of the maximum transformation unit size information, minimum transformation unit size information and maximum TU size TU flag can be entered into an SPS. According to an exemplary embodiment, a video decoding apparatus 200 can decode video using the maximum transform unit size information, the minimum transform unit size information and the maximum TU size flag.

[000150] For example, if the size of a current encoding unit is 64x64 and a maximum transform unit size is 32x32, the size of a transform unit can be 32x32 when a TU size flag is 0, it can be 16x16 when the TU size flag is 1 and it can be 8x8 when the TU size flag is 2.

[000151] As another example, if the current decoding unit size is 32x32 and a minimum transform unit size is 32x32, the transform unit size can be 32x32 when the TU size flag is set to 0. Here, the transform unit size can be 32x32. TU size flag cannot be set to a value other than 0, as the transformation unit size cannot be smaller than 32x32.

[000152] As another example, if the current encoding unit size is 64x64 and a maximum TU size flag is 1, the TU size flag can be either 0 or 1. Here, the TU size flag cannot be set to a value other than 0 or 1.

[000153] So if it is defined that the maximum TU size flag is MaxTransformSizendex, a minimum transformation unit size is MinTransformSize and a transformation unit size is RootTuSize when the TU size flag is 0, then a size of current minimum transform unit CurrMinTuSize which can be determined in a current encoding unit, can be defined by Equation (1):CurrMinTuSize = max( MinTransformSize, RtxitTuSizr/ (2AMaxTransformSizelndex)) (1).

[000154] Compared to the current CurrMinTuSize minimum transform unit size that can be determined in the current encoding unit, a RootTuSize transform unit size when the TU size flag is 0 can denote a maximum transform unit size that can be selected in the system. In Equation (1) , RootTuSize/(2AMaxTransformSizelndex) denotes a transformation unit size when the RootTuSize transformation unit size, when the TU size flag is 0, is divided a series of times corresponding to the maximum TU size flag and MinTransformSize denotes a minimum transform size. So, a smaller value between RootTuSize/(2AMaxTransformSizelndex) and MinTransformSize can be the current minimum transform unit size CurrMinTuSize that can be determined in the current encoding unit.

[000155] According to an exemplary embodiment, the maximum RootTuSize transform unit size can vary according to the type of a prediction mode. For example, if a current prediction mode is an inter mode, then RootTuSize can be determined using Equation (2) below. In Equation (2), MaxTransformSize denotes a maximum transform unit size and PUSize denotes a current prediction unit size:RootTuSize - mint MaxTransformSize, PUSize)......... (2).

[000156] That is, if the current prediction mode is inter mode, the RootTuSize transformation unit size when the TU size flag is 0 can be a smaller value between the maximum transformation unit size and the size of the current prediction unit: If a prediction mode of a current partition unit is an intra mode, RootTuSize can be determined using Equation (3) below. In Equation (3), PartitionSize denotes the size of the current partition drive:RootTuSize = miniMaxTransformSize, PartitionSize) (3).

[000157] That is, if the current prediction mode is intra mode, the RootTuSize transformation unit size when the TU size flag is 0 can be a smaller value between the maximum transformation unit size and the size of the current partition drive.

[000158] However, RootTuSize maximum transform unit size that varies according to the type of a prediction mode in a partition unit is just an example and it is understood that other exemplary modality is not limited to the same.

[000159] FIG. 14 is a flowchart illustrating a method of encoding a video in accordance with an exemplary embodiment. With reference to FIG. 14, at operation 1210, a current image is divided into at least one maximum encoding unit. The maximum depth indicating a total number of possible division times can be predetermined.

[000160] In operation 1220, an encoded depth to produce a final encoding result according to at least one divided region which is obtained by dividing a region of each maximum encoding unit according to depths is determined by encoding the at least one region divided and an encoding unit according to a tree structure is determined.

[000161] The maximum encoding unit is spatially divided whenever the depth goes deeper and therefore is divided into encoding units of a lower depth. Each encoding unit can be divided into encoding units of another lower depth by being spatially divided independently of adjacent encoding units. Encoding is performed repeatedly on each encoding unit according to depths.

[000162] Also, a transformation unit according to partition types having a minimum coding error is determined for each deeper coding unit. In order to determine an encoded depth having the minimum encoding error in each maximum encoding unit, encoding errors can be measured and compared in all deeper encoding units according to depths.

[000163] In operation 1230, the encoded image data corresponding to the final encoding result according to the encoded depth is sent to each maximum encoding unit with encoding information regarding the encoded depth and an encoding mode. Information about the encoding mode can include at least one of information about an encoded depth or split information, information about a partition type of a prediction unit, a prediction mode, and a size of a unit of prediction. transformation. Encoding information about the encoding mode can be transmitted to a decoder with the encoded image data.

[000164] FIG. 15 is a flowchart illustrating a method for decoding a video in accordance with an exemplary embodiment. With reference to FIG. 15, at operation 1310, an encoded video bit stream is received and analyzed.

[000165] In operation 1320, the encoded image data of a current image assigned to a maximum encoding unit and information regarding an encoded depth and an encoding mode according to the maximum encoding units is extracted from the stream. bits analyzed. The encoded depth of each maximum encoding unit is a depth having a minimum encoding error in each maximum encoding unit. In encoding each maximum encoding unit, the image data is encoded based on at least one data unit obtained by hierarchically dividing the maximum encoding unit according to depths.

[000166] According to the information regarding encoded depth and encoding mode, the maximum encoding unit can be divided into encoding units having a tree structure. Each of the coding units having the tree structure is determined as a coding unit corresponding to a coded depth and is perfectly coded so as to emit minimal coding errors. Thus, the efficiency of encoding and decoding an image can be improved by decoding each of the encoded image data in the encoding units after determining at least one encoded depth according to encoding units.

[000167] In operation 1330, the image data of each max coding unit is decoded based on the information regarding the encoded depth and the coding mode according to the max coding units. For example, decoded image data can be played back by a playback device, stored on a storage medium or transmitted over a network.

[000168] Now, video encoding and decoding performed using encoding unit pattern information regarding a encoding unit according to a tree structure, according to another exemplary embodiment, will be described in detail with reference to FIGS . 16 to 29.

[000169] FIG. 16 is a block diagram of a video encoding apparatus 1400 using encoding unit pattern information in accordance with an exemplary embodiment. With reference to FIG. 16, video encoding apparatus 1400 includes maximum encoding unit splitter 1410, encoded unit determiner 1420, and output unit 1460. Output unit 1460 includes encoded image data output unit 1430, a coding information output unit 1440 and a coding unit pattern information output unit 1450.

[000170] The maximum coding unit divider 1410 and the coded unit determiner 1420 correspond to the maximum coding unit divider 110 and the coded unit determiner 120 included in the video encoding apparatus 100 illustrated in FIG. 1, respectively. The operations of the encoded picture data output unit 1430 and the encoding information output unit 1440 may be the same or similar to at least some of the operations of the output unit 130 included in the video encoding apparatus 100 of FIG. 1. An exemplary embodiment in which the encoding unit pattern information output unit 1450 encodes the encoding unit pattern information will now be described.

[000171] In the present exemplary embodiment, the maximum encoding unit divider 1410 divides a current image from an image, based on a maximum encoding unit for the current image. The coding unit determiner 1420 determines at least one coded depth by encoding image data in coding units according to depths in each maximum coding unit selecting a depth having the least coding errors. Thus, the coding unit determiner 1420 can determine the coding units, having a tree structure, included in each maximum coding unit.

[000172] The encoded image data output unit 1430 sends a bit stream of the encoded image data according to the encoded depth in each maximum encoding unit. The coding information output unit 1440 encodes and sends information regarding coding modes according to coded depths in each maximum coding unit.

[000173] Encoding unit pattern information output unit 1450 encodes and sends encoding unit pattern information indicating whether the texture information for each of the maximum encoding units has been encoded. Texture information includes, for example, at least one of a quantization parameter, a transformation coefficient, and a transformation index for a data unit.

[000174] If the video encoding apparatus 1400 according to the current exemplary embodiment corresponds to the picture encoder 400 of FIG. 4 , then, motion estimated/compensated data is generated from image data corresponding to a current encoding unit using intrapredictor 410, motion estimator 420, and motion compensator 425 of FIG. 4. The motion estimated/compensated data is transformed by transformer 430 and then quantized by quantizer 440, thereby generating a current encoding unit transformation coefficient.

[000175] Encoding unit pattern information regarding current encoding unit can be set based on whether all current encoding unit transform coefficients are 0. Current encoding unit transform coefficients that are defined to be encoded according to encoding unit pattern information can be entered into entropy encoder 450 to be sent in a bit stream.

[000176] Encoding unit pattern information is used in order to determine whether the encoded texture will be transmitted when texture information is not encoded in encoding units or when texture information is encoded in encoding units. For example, if all the transform coefficients in the encoding units are 0, then the encoding unit pattern information is adjusted to indicate that the texture information will not be encoded. However, if any of the transform coefficients in the encoding unit is not 0, then the encoding unit pattern information is adjusted to indicate that the texture information has been encoded.

[000177] According to an exemplary embodiment, examples of the encoding unit pattern information include encoding unit pattern information corresponding to an encoded depth and hierarchical encoding unit pattern information.

[000178] Encoding unit pattern information corresponding to an encoded depth is set to encoding units corresponding to at least one encoded depth in a maximum encoding unit and indicates whether texture information of an encoding unit corresponding to a depth encoded were encoded. For example, encoding unit pattern information corresponding to an encoded depth may indicate whether all transformation coefficients in encoding units according to depths up to an encoded depth are 0.

[000179] Hierarchical encoding unit pattern information is set to at least one transformation depth, respectively. A transformation depth of a maximum transformation unit is from a higher transformation depth and a transformation unit divides as a transformation depth becomes deeper. Also, a transform unit of a current transform depth can include four transform units, whose depths are lower by one layer than the current transform depth.

[000180] Hierarchical encoding unit pattern information corresponding to a current transformation depth indicates whether hierarchical encoding unit pattern information relative to transformation units from lower depths in a layer has been encoded. The coding unit pattern information output unit 1450 sets and encodes hierarchical coding unit pattern information for each of the transformation depths ranging from a higher transformation depth to a lower transformation depth or to a predetermined depth.

[000181] For example, the hierarchical encoding unit pattern information can be set for each of the depths, and the texture information of a transform unit corresponding to the lowest transform depth can be encoded.

[000182] The transformation depth of a transformation unit can be linked to a depth and an encoded depth of a corresponding encoding unit. For example, a transform depth can be set to be fixedly equal to or less than a layer at a depth of one encoding unit. Otherwise, a transform depth can be set to be different from a depth of an encoding unit.

[000183] According to an exemplary embodiment, in the video encoding apparatus 1400, if only one or both of the encoding unit pattern information corresponding to an encoded depth and the hierarchical encoding unit pattern information are to be encoded , can be selectively adjusted by at least one data unit selected from a GOP, an image, a slice and a maximum encoding unit.

[000184] For example, if both encoding unit pattern information corresponding to an encoded depth and hierarchical encoding unit pattern information are used, then unit encoding unit pattern information output 1450 can adjust hierarchical encoding unit pattern information for each of the depths ranging from a greater depth to an encoded current depth and can adjust and encode encoding unit pattern information corresponding to an encoded depth to an encoding unit corresponding to the current depth encoded.

[000185] The encoding unit corresponding to the encoded depth may include at least one transformation unit. Transform unit pattern information, indicating whether texture information has been encoded, can be set to at least one transform unit, respectively. For example, transformation unit pattern information indicates whether a current transformation unit includes a transformation coefficient other than 0.

[000186] When the texture information of transform units is to be encoded, the encoding unit pattern information output unit 1450 can set transform unit pattern information for each of the transform units and can adjust and encode encoding unit pattern information corresponding to an encoded depth of an encoding unit that includes the transform units.

[000187] If all the transform coefficients in the encoded depth encoding unit are not 0, then the encoded image data output unit 1430 may not send encoded texture information. According to an exemplary embodiment, if all of the transform units belonging to a coding unit corresponding to the encoded depth do not include transform coefficients other than 0, then the coding unit pattern information output unit 1450 does not encode the transform unit pattern information to the encoding unit corresponding to the encoded depth. On the contrary, the encoding unit pattern information output unit 1450 can set and encode encoding unit pattern information corresponding to the encoded depth, which indicates that the encoding unit texture information corresponding to the encoded depth will not be encoded, to the encoding unit corresponding to the encoded depth.

[000188] The encoding unit pattern information corresponding to the encoded depth can be adjusted according to the color components of the image data. For example, the encoding unit pattern information corresponding to the encoded depth can be set for both a luma component and a chroma component, or can be set for each of the luma components, the chroma component, a first chroma component and a second chroma component (see FIGS. 18 to 26 for a more detailed description).

[000189] Encoding unit pattern information to which one or more bits are assigned can be set in one of the encoding units according to depths and transform units for each of the maximum encoding units.

[000190] FIG. 17 is a block diagram of a video decoding apparatus 1500 using encoding unit pattern information in accordance with an exemplary embodiment. With reference to FIG. 17, video decoding apparatus 1500 includes a receiver 1501, an extractor 1505 and an image data decoder 1540. The extractor 1505 includes an image data acquisition unit 1510, an encoding information extractor 1520 and an extractor. 1530 encoding unit pattern information.

[000191] Receiver 1501 and picture data decoder 1540 correspond to receiver 210 and picture data decoder 230 included in video decoding apparatus 200 of FIG. 2, respectively. The operations of the image data acquisition unit 1510, the encoding information extractor 1520 and the image data decoder 1540 are the same or similar to at least some of the operations of the image data information extractor and encoding 220 of the video decoding apparatus 200 of FIG. 2. A method of performing decoding using encoding unit pattern information extracted by encoding unit information extractor 1530 in accordance with an exemplary embodiment will now be described with reference to FIG. 17 .

[000192] Receiver 1501 receives and analyzes an encoded video bit stream. Extractor 1505 extracts various types of encoding information from the bitstream parsing result. The image data acquisition unit 1510 can obtain image data that has been encoded in units of maximum encoding units from the result of bitstream analysis. The encoding information extractor 1520 analyzes the bit stream and then extracts information about an encoded depth and encoding mode for each of the maximum encoding units from a header of a current image.

[000193] Encoding unit pattern information extractor 1530 extracts encoding unit pattern information indicating whether texture information from a maximum encoding unit has been encoded, for each of the maximum encoding units. The encoding unit pattern information extractor 1530 can extract encoding unit pattern information corresponding to an encoded depth and hierarchical encoding unit pattern information regarding a current maximum encoding unit, such as encoding unit.

[000194] Whether only one or both encoding unit pattern information corresponding to an encoded depth and hierarchical encoding unit pattern information will be extracted can be set in units of a GOP, an image, a slice or a unit maximum encoding.

[000195] For example, a unit of encoding unit pattern information corresponding to an encoded depth can be extracted against a encoding unit according to an encoded depth, or a hierarchical encoding unit pattern information unit can be extracted with respect to each of the depths ranging from a depth greater than the encoded depth. A unit of encoding unit pattern information may be predetermined bits. For each of the maximum encoding units, one or more bits of the encoding unit pattern information can be set in each of the encoding units according to depths or a transform unit. For example, if encoding unit pattern information is in the form of flags, then one unit of encoding unit pattern information can be a bit.

[000196] The picture data decoder 1540 reconstructs the current picture by decoding the picture data that has been encoded in units of maximum encoding units, based on information regarding encoded depths and encoding modes of the maximum encoding units and in the encoding unit pattern information.

[000197] According to an exemplary embodiment, the picture data decoder 1540 can check at least a coded depth of the current maximum coding unit and can detect hierarchical structures of coding units according to depths of a tree structure included in the current maximum coding unit based on information regarding the coded depths and coding modes of the maximum coding units.

[000198] In addition, the image data decoder 1540 can decode the encoded image data by performing an inverse transformation on a transformation coefficient included in the maximum encoding unit texture information extracted by the pattern information extractor. encoding unit 1530 based on the encoding unit pattern information against the maximum encoding unit.

[000199] If the picture data decoder 1540 corresponds to the picture decoder 500 of FIG. 5, then, the transformation coefficient included in the texture information of encoding units can be inversely transformed into time domain data using inverse quantizer 530 and inverse transformer 540.

[000200] That is, if the encoding unit pattern information indicates that the texture information of the current encoding unit has been encoded according to the encoding unit pattern information, then the picture data decoder 1540 can receiving a transform coefficient that has been entropy decoded from entropy decoder 520 of picture decoder 500 of FIG. 5 and perform inverse transformation on the transformation coefficient to obtain data in the spatial domain. Time domain data may be reconstructed into a reconstructed frame using intrapredictor 550, motion compensator 560, unlocking unit 570, and in-circuit filtering unit 580 of image decoder 500 of FIG. 5.

[000201] Encoding unit pattern information extractor 1530 can detect at least one of encoding pattern information from a coded depth and hierarchical encoding pattern information such as encoding unit pattern information in relation to encoding units. encoding according to coded depths to the current maximum encoding unit.

[000202] If encoding pattern information according to an encoded depth is detected, then the picture data decoder 1540 can determine a encoding unit decoding method corresponding to the current encoded depth based on the encoding pattern information. encoding detected according to an encoded depth.

[000203] For example, if it is determined based on the encoding pattern information detected according to an encoded depth that the texture information of the encoding unit corresponding to the current encoded depth was not encoded, then the image data decoder 1540 can decode the encoding unit corresponding to the current encoded depth by referring to information regarding a data unit adjacent to the encoding unit corresponding to the actual encoded depth.

[000204] Also, if it is determined on the basis of the encoding pattern information detected according to an encoded depth that the texture information of the encoding unit corresponding to the current depth has been encoded, then the picture data decoder 1540 can decoding the encoding unit corresponding to the current encoded depth by performing inverse transformation on a transformation coefficient included in the encoded texture information of the encoding unit corresponding to the encoded current depth.

[000205] Also, if hierarchical coding pattern information is detected, the image data decoder 1540 can determine if hierarchical coding pattern information with respect to a transformation depth less than a current transformation depth is present and determining a method for decoding a transformation unit corresponding to the current transformation depth based on the determined hierarchical encoding unit pattern information.

[000206] For example, if it is determined from the detected hierarchical encoding unit pattern information corresponding to the current transform unit that hierarchical encoding pattern information regarding the lower depth of the current transform depth is present, then the picture data decoder 1540 can check the hierarchical encoding pattern information with respect to the lower transformation depth. However, if it is determined from the detected hierarchical encoding unit pattern information corresponding to the current transform unit that the hierarchical encoding pattern information with respect to the lower depth of the current transform depth is not present, then the decoder image dataset 1540 can decode the current transform unit corresponding to the current transform depth.

[000207] If both encoding unit pattern information corresponding to an encoded depth and hierarchical encoding unit pattern information are detected, then the picture data decoder 1540 can check whether the hierarchical encoding pattern information with respect to a transformation depth less than the current transformation depth were encoded based on the hierarchical encoding unit pattern information relative to the current transformation depth.

[000208] If it is determined that hierarchical encoding pattern information with respect to the lower transform depth is present, then the hierarchical encoding pattern information with respect to the lower transform depth can be verified. If it is determined on the basis of the hierarchical encoding unit pattern information corresponding to the current transformation depth that the hierarchical encoding pattern information with respect to the lower transformation depth is not present, then the picture data decoder 1540 can decode the transformation unit corresponding to the current transformation depth, based on encoding unit pattern information related to the transformation unit corresponding to the current transformation depth.

[000209] Also, if the current transform depth is the lowest depth or a preset final depth, then the transform unit corresponding to the current transform depth can be set to be decoded independently of the encoding pattern information hierarchical according to depths of transformation. If the transformation unit corresponding to the current transformation depth is decoded, then texture information, for example, a quantization parameter, a transformation coefficient, a transformation index, etc., can be decoded.

[000210] The encoding unit corresponding to the encoded depth may include at least one transform unit and can be decoded by performing inverse transform based on transform unit pattern information that is set in each of the at least one unit of transformation. That is, whether the texture information of a desired transform unit has been encoded can be determined based on the transform unit pattern information.

[000211] Thus, if it is determined from the encoding unit pattern information corresponding to the encoded depth that the encoding unit has encoded texture information, then the picture data decoder 1540 checks the encoding unit pattern information. transformation of each of the transformation units of the encoding unit.

[000212] If it is determined based on the transform unit pattern information that the desired transform unit has encoded texture information, then the picture data decoder 1540 can perform an inverse transformation on a transform unit transform coefficient. desired transformation. If it is determined based on the transform unit pattern information that the desired transform unit does not have encoded texture information, then image data decoder 1540 can decode encoded image data of the desired transform unit using information about it. of a processing unit adjacent to the desired processing unit.

[000213] If it is determined from the encoding unit pattern information corresponding to the encoded depth that the desired transform unit has no encoded texture information, then the transform unit pattern information regarding all transformation units transformation of the desired encoding unit were not encoded. In this case, the picture data decoder 1540 may not detect the transform unit pattern information for each of the transform units of the desired encoding unit.

[000214] In the video encoding apparatus 1400 and in the video decoding apparatus 1500 in accordance with exemplary embodiments, encoding unit pattern information or transforming unit pattern information which has been encoded based on encoding units in accordance with with tree structures and transformation units can be used. Thus, it is possible to determine whether the transform unit pattern information of each of the transform units has been encoded based on encoding unit pattern information which is set to an encoding unit having a plurality of groups of transform units. . As the number of encoding units is less than the number of transformation units, setting encoding unit pattern information for each of the encoding units reduces the amount of data than when setting the encoding unit pattern information for each of the encoding units. transformation for each of the transformation units, thereby improving bit transmission efficiency.

[000215] Encoding unit pattern information corresponding to an encoded depth that is adjusted according to color components of image data in accordance with exemplary embodiments will now be described with reference to FIGS. 18 to 26. It is assumed in the following exemplary embodiment that a unit of encoding unit pattern information is a bit, but it is understood that another exemplary embodiment is not limited thereto.

[000216] FIGS. 18 to 20 are block diagrams illustrating encoding unit pattern information corresponding to an encoded depth when an encoding unit corresponding to an encoded depth includes a transforming unit in accordance with one or more exemplary embodiments.

[000217] With reference to FIGS. 18 to 20, a first color image data encoding unit according to YCbCr color standards includes a luma component encoding unit 1600, a first component chroma encoding unit 1610, and a second component chroma encoding unit 1600. 1620 having a second chroma component.

[000218] If a transformation unit of the first encoding unit is equal to the first encoding unit in size, then the first encoding unit includes only one transformation unit. Thus, the first encoding unit transform unit includes a luma component transform unit 1605, a first component chroma transform unit 1615, and a second component chroma transform unit 1625. The transform unit pattern information may be set for each of the component luma transform unit 1605, the first component chroma transform unit 1615 and the second component chroma transform unit 1625.

[000219] Referring to FIG. 18, encoding unit pattern information corresponding to an encoded depth is not further encoded for the first encoding unit. In this case, an encoding unit pattern information output unit 1450 of FIG. 16 does not send encoding unit pattern information corresponding to an encoded depth for the first encoding unit. The picture data decoder 1540 of FIG. 17 can only check the transform unit pattern information for each of the luma component transform unit 1605, the first component chroma transform unit 1615 and the second component chroma transform unit 1625 and perform an inverse transform on the transform coefficients of the luma component transform unit 1605, the first component chroma transform unit 1615 and the second component chroma transform unit 1625, based on the verification result, without verifying the corresponding encoding unit pattern information to an encoded depth for the first encoding unit.

[000220] Referring to FIG. 19, 1-bit encoding unit pattern information corresponding to an encoded depth is set to a group 1630 to which a component luma transform unit 1600, a first component chroma transform unit 1610, and a second transform unit chroma component 1620 of a first encoding unit belong. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends the 1-bit encoding unit pattern information corresponding to an encoded depth to the first encoding unit.

[000221] Referring to FIG. 20, 1-bit encoding unit pattern information corresponding to an encoded depth is set to each of a group 1640 to which a luma component encoding unit 1600 of a first encoding unit belongs, and a group 1650 to which to which a first component chroma encoding unit 1610 and a second component chroma encoding unit 1620 of the first encoding unit belong. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends a 2-bit encoding unit pattern information corresponding to an encoded depth to the first encoding unit.

[000222] In accordance with an exemplary embodiment, the picture data decoder 1540 of FIG. 17 can determine whether a desired encoding unit includes encoded texture information or by checking 1-bit encoding unit pattern information corresponding to an encoded depth of FIG. 19 or the 2-bit encoding unit pattern information corresponding to an encoded depth of FIG. 20, for a first encoding unit. If the desired encoding unit includes encoded texture information, then the picture data decoder 1540 of FIG. 17 can verify transformation unit pattern information of a corresponding transformation unit and perform inverse transformation on the corresponding transformation coefficients based on the verification result.

[000223] FIGS. 21 to 23 illustrate encoding unit pattern information corresponding to an encoded depth when an encoding unit corresponding to the encoded depth includes four transform units in accordance with exemplary embodiments. With reference to FIGS. 21 to 23, a second color image data encoding unit in accordance with the YCbCr color standards includes a luma component encoding unit 1700, a first component chroma encoding unit 1710, and a second component encoding unit. chroma 1720.

[000224] If the second encoding unit includes four transformation units, then each of the encoding units of the second encoding unit, which are classified according to a color component, also includes four transformation units. That is, the component luma encoding unit 1700 includes four component luma transform units 1702, 1704, 1706 and 1708, the first component chroma encoding unit 1710 includes four first component chroma transform units 1712, 1714, 1716 and 1718, and the second component chroma encoding unit 1720 includes four second component chroma transform units 1722, 1724, 1726 and 1728.

[000225] Referring to FIG. 21, the 1-bit encoding unit pattern information corresponding to an encoded depth is defined by a group of 1730 to which only the encoding component 1700 of a unit of the second encoding unit belongs. However, the encoding unit pattern information corresponding to an encoding depth is not adjusted for the first 1710 chroma component encoding unit and the second 1720 chroma component encoding unit.

[000226] In this case, the coding unit pattern information output unit 1450 of FIG. 16 sends 1-bit encoding unit pattern information corresponding to the encoded depth relative to the luma component encoding unit 1700. Thus, the picture data decoder 1540 of FIG. 17 checks the 1-bit encoding unit pattern information corresponding to the encoded depth against the luma component encoding unit 1700 and determines whether the encoded texture information is present in the luma component encoding unit 1700. If it is determined that encoded texture information is present, then picture data decoder 1540 can check the transform unit pattern information of luma component transform units 1702, 1704, 1706 and 1708, and perform inverse transform on the transform coefficients of processing units 1702, 1704, 1706 and 1708 based on the result of the verification.

[000227] Alternatively, the picture data decoder 1540 may check only transform unit pattern information from the first component chroma transform units 1712, 1714, 1716 and 1718 and the second component chroma transform units 1722, 1724, 1726 and 1728 and can perform an inverse transform on the transform coefficients of transform units 1712, 1714, 1716, 1718, 1722, 1724, 1726 and 1728 based on the verification result, without verifying encoding unit pattern information corresponding to an encoded depth of the first chroma component 1710 and second of the second chroma component 1720 of the second encoding unit.

[000228] Referring to FIG. 22, 1-bit encoding unit pattern information corresponding to an encoded depth is set to a group 1740 to which a luma component encoding unit 1700, a first chroma component encoding unit 1710, and a second chroma encoding unit are set. chroma component 1720 of a second encoding unit belong. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends the 1-bit encoding unit pattern information corresponding to an encoded depth to the second encoding unit.

[000229] Referring to FIG. 23, 1-bit encoding unit pattern information corresponding to an encoded depth is set for each of a group 1750 to which a luma component encoding unit 1700 of a second encoding unit belongs, a group 1760 to which a first component chroma encoding unit 1710 of the second encoding unit belongs, and a group 1770 to which a second component chroma encoding unit 1720 of the second encoding unit belongs. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends 3-bit encoding unit pattern information corresponding to an encoded depth to the second encoding unit.

[000230] The picture data decoder 1540 of FIG. 17 can determine whether encoded texture information is present in an encoding unit by checking either the 1-bit encoding unit pattern information corresponding to the encoded depth (see FIG. 22) or the 3-bit encoding unit pattern information. bits corresponding to the encoded depth (see FIG. 23) for the second encoding unit. If it is determined that encoded texture information is present, then the picture data decoder 1540 can check the transform unit pattern information of transform units corresponding to the encoding unit and perform an inverse transform on the transform coefficients of the units. transformation based on the verification result.

[000231] FIGS. 24 to 26 illustrate encoding unit pattern information corresponding to an encoded depth, when an encoding unit corresponding to the encoded depth includes a plurality of transform units in accordance with exemplary embodiments. With reference to FIGS. 24-26, the third color image data encoding unit in accordance with YCbCr standards includes a luma component encoding unit 1800, a first component chroma encoding unit 1820, and a second component chroma encoding unit 1830.

[000232] If the third encoding unit includes at least four transform units, then luma component encoding unit 1800 of the third encoding unit also includes at least four transform units. That is, the number of transform units of the luma component encoding unit 1800 is equal to the number of transform units of the third encoding unit. For example, if the third encoding unit includes sixteen transform units, then the luma component encoding unit 1800 also includes sixteen luma component transform units 1801, 1802, 1803, 1804, 1805, 1806, 1807, 1808, 1809, 1810, 1811, 1812, 1813, 1814, 1815 and 1816.

[000233] Each of the first component chroma encoding unit 1820 and the second component chroma encoding unit 1830 may include four transform units. That is, the first component chroma encoding unit 1810 may include four first component chroma transform units 1822, 1824, 1826 and 1828, and the second component chroma encoding units 1830 may include four second component chroma transform units 1830 1832, 1834, 1836 and 1838.

[000234] A unit of encoding unit pattern information corresponding to an encoded depth can be set as encoding unit pattern information corresponding to an encoded depth for a part of luma component encoding unit 1800, for a group at to which a predetermined number of luma component transform units belong. For example, encoding unit pattern information corresponding to an encoded depth can be set for each of the groups to which four luma component transform units of luma component encoding unit 1800 belong. That is, in luma component encoding unit 1800, 1-bit encoding unit pattern information can be set for each of a group 1840 to which four transform units 1801, 1802, 1803, and 1804 belong, a group 1850 to which four transformation units 1805, 1806, 1807 and 1808 belong, a group 1860 to which four transformation units 1809, 1810, 1811 and 1812 belong, and a group 1870 to which four transformation units 1813, 1814, 1815 and 1816 belong.

[000235] Referring to FIG. 24, the encoding unit pattern information corresponding to an encoded depth is not set for the first 1820 component chroma encoding unit and the second 1830 component chroma encoding unit.

[000236] In this case, the coding unit pattern information output unit 1450 of FIG. 16 sends 4-bit encoding pattern information corresponding to the encoded depth to groups 1840, 1850, 1860, and 1870 of luma component encoding unit 1800. Image data decoder 1540 of FIG. 17 checks the 4-bit encoding pattern information corresponding to the encoded depth and determines whether encoded texture information is present for each of groups 1840, 1850, 1860, and 1870.

[000237] Alternatively, the picture data decoder 1540 can check the transform unit pattern information of the first component chroma transform units 1822, 1824, 1826 and 1828 and the second component chroma transform units 1832, 1834, 1836 and 1838 without checking the pattern information corresponding to the encoded depth for the encoding unit 1830 of the first chroma component 1820 and the second chroma component 1830.

[000238] Referring to FIG. 25, in a third encoding unit, 1-bit encoding unit pattern information corresponding to an encoded depth is set for each of a plurality of groups of luma component encoding units 1840, 1850, 1860, and 1870, a group 1880 to which a first component chroma encoding unit 1820 belongs and a group 1885 to which a second component chroma encoding unit 1830 belongs. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends 6-bit encoding unit pattern information corresponding to the encoded depth to the third encoding unit.

[000239] Referring to FIG. 26, in a third encoding unit, 1-bit encoding unit pattern information corresponding to an encoded depth is set for each of a plurality of luma component encoding unit groups 1840, 1850, 1860, and 1870 and a group 1890 to which a first component chroma encoding unit 1820 and a second component chroma encoding unit 1830 belong. In this case, the encoding unit pattern information output unit 1450 of FIG. 16 sends 5-bit encoding unit pattern information corresponding to the encoded depth to the third encoding unit.

[000240] The picture data decoder 1540 of FIG. 17 determines whether encoded texture information is present for the encoding unit by checking either the 6-bit encoding unit pattern information corresponding to the encoded depth (see FIG. 25) or the 5-bit encoding unit pattern information. corresponding to the encoded depth (see FIG. 26) for the third encoding unit. If it is determined that encoded texture information is present, picture data decoder 1540 can verify transform unit pattern information from a transform unit included in the encoding unit and perform an inverse transform on the transform coefficients of the transform units. transformation based on the scan result.

[000241] As described above, according to one or more exemplary embodiments, encoding unit pattern information may be set for each of the color components and a plurality of encoding unit pattern information of the same encoding unit, which are classified according to a color component, can be combined and coded.

[000242] In a video encoding apparatus 100 and a video decoding apparatus 200 according to exemplary embodiments, a plurality of encoding unit pattern information that is categorized according to a color component may be encoded or decoded accordingly. an integrated form based on the relationship between encoding unit pattern information about a luma component, first chroma component and second chroma component of the same encoding unit and the relationship between encoding unit pattern information thereof color component with respect to neighboring encoding units.

[000243] For example, for variable length encoding (VLC) of a current encoding unit, encoding unit pattern information about a luma component, encoding unit pattern information about a first component of Chroma and encoding unit pattern information about a second chroma component can be combined and encoded using a codeword.

[000244] Furthermore, by way of example, a VLC table can be configured in such a way that different unary codewords correspond to combinations of a plurality of encoding unit pattern information that are classified according to a color component , respectively. Thus, the plurality of encoding unit pattern information can be encoded in an integrated manner. A VLC table can be selected such that the shorter a unary codeword, the greater the probabilities of combinations of the plurality of encoding unit pattern information.

[000245] As described above, it is possible to improve coding efficiency by encoding or decoding a plurality of coding unit pattern information that is classified according to a color component in an integrated manner based on the relationship between a plurality of information coding unit pattern information of the same coding unit that are classified according to a color component and the relationship between a plurality of coding unit pattern information of the same color component of neighboring coding units.

[000246] According to an exemplary embodiment, encoding unit pattern information corresponding to an encoded depth is set in a encoding unit corresponding to the encoded depth, hierarchical encoding unit pattern information is set in transform units accordingly with transform depths that are divided from the encoding unit corresponding to the encoded depth, and the transform unit pattern information is adjusted into a final transform unit.

[000247] Thus, encoding unit pattern information corresponding to encoded depth, hierarchical encoding unit pattern information, and transformation unit pattern information can be continuously defined based on the hierarchical structures of a unit encoding and a transformation unit according to an exemplary embodiment.

[000248] Thus, in the video encoding apparatus 100 and in the video decoding apparatus 200 according to exemplary embodiments, it is possible to determine whether a texture component which is not 0 and which is included from an encoding unit to a unit transformation has been encoded using a data unit pattern information that is hierarchically defined according to a transformation depth, without differentiating the encoding unit pattern information corresponding to the encoded depth, the hierarchical encoding unit pattern information, and each other's transform unit pattern information.

[000249] FIG. 27 is a diagram illustrating hierarchical encoding unit pattern information according to an exemplary embodiment. With reference to FIG. 27 transformation units 1912, 1914, 1916, 1918, 1920, 1930, 1942, 1944, 1946, 1948, 1954, 1956 and 1958, whose sizes are determined according to corresponding transformation depths, respectively, are defined for a unit of maximum encoding 1900.

[000250] For example, a transform unit corresponding to transform depth of 0 is equal to the maximum encoding unit 1900 in size, although the maximum encoding unit 1900 illustrated in FIG. 27 do not include the transform unit corresponding to the transform depth of 0.

[000251] The transformation units 1920 and 1930 are equal to the result of dividing the height and width of the transformation unit corresponding to the transformation depth of 0 into two equal parts, and correspond to a transformation depth of 1. In the same way , the transformation units 1912, 1914, 1916, 1918, 1954, 1956 and 1958 correspond to a transformation depth of 2 and the transformation units 1942, 1944, 1946 and 1948 correspond to a transformation depth of 3.

[000252] Hierarchical encoding unit pattern information indicates whether hierarchical encoding unit pattern information regarding a lower transformation depth should be encoded. Also, the hierarchical encoding unit pattern information can reveal whether texture information from the lower transform depth has been encoded.

[000253] The maximum encoding unit 1900 does not include the transform unit corresponding to transform depth of 0 and uses texture information from a transform unit corresponding to transform depth of 1 which is less than transform depth of 0. So , 1-bit 1960 hierarchical encoding unit pattern information is set to transform depth of 0.

[000254] With respect to transform depth of 1, transform unit 1920 and 1930 are decoded at transform depth of 1 and therefore texture information from a transform unit corresponding to transform depth of 2 which is less than transformation depth 1 cannot be encoded. Also, hierarchical encoding unit pattern information regarding the transform depth of 2 may not be defined. Thus, hierarchical encoding unit pattern information of 1 bit with respect to transform depth of 1, which indicates that the texture information of hierarchical encoding unit pattern information with respect to transform depth of 2 may not be coded, are provided for each of the 1920 and 1930 transformer units.

[000255] However, texture information from a transform unit corresponding to a transform depth of 2, which is less than a transform depth of 1, must be encoded for each of a group, corresponding to a transform depth of 1, to which the transformation units 1912, 1914, 1916 and 1918 corresponding to transformation depth of 2 belong, and a group corresponding to transformation depth of 1 to which transformation units 1942, 1944, 1946, 1948, 1954 and 1956 , and 1958 belong. Thus, coding unit pattern information with respect to transform depth of 2 can be encoded and 1-bit hierarchical coding unit pattern information with respect to transform depth of 1 can be set for each of the groups of way to indicate this fact.

[000256] Thus, a total of 1970 hierarchical encoding unit pattern information is set to the transform depth of 1.

[000257] Regarding the transform depth of 2, the transform units 1912, 1914, 1916, 1918, 1954, 1956 and 1958 can be decoded at the transform depth of 2. For this reason, texture information from a unit of transformation corresponding to the transformation depth of 3 which is less than the transformation depth of 2 cannot be encoded, and thus hierarchical encoding unit pattern information regarding the transformation depth of 3 cannot be set. Thus, the hierarchical encoding unit pattern information of 1 bit with respect to the transform depth of 2 can be set for each of the transform units 1912, 1914, 1916, 1918, 1954, 1956, and 1958, so that indicate that hierarchical encoding unit pattern information with respect to the transformation depth of 3 cannot be encoded.

[000258] However, information from a transform unit corresponding to transform depth of 3 can be encoded to a group, corresponding to transform depth of 2, to which transform units 1942, 1944, 1946 and 1948 belong. Thus, coding unit pattern information about the transform depth of 3 can be encoded and 1-bit hierarchical coding unit pattern information about the transform depth of 2 can be defined so as to indicate this fact. .

[000259] Therefore, a total of 1980 8-bit hierarchical encoding unit pattern information can be set to the transform depth of 2.

[000260J Transformation depth of 3 is a final transformation depth, and therefore 1-bit hierarchical encoding unit pattern information about transformation depth of 3 can be set for each of the 1942 transformation units, 1944, 1946 and 1948 so as to indicate that hierarchical encoding unit pattern information regarding a lower transformation depth cannot be encoded. Thus, a total of 4-bit 1990 hierarchical encoding unit pattern information can be set to the transform depth of 3.

[000261] Fig. 28 is a flowchart illustrating a method of encoding video data using encoding unit pattern information according to an exemplary embodiment. Referring to Fig. 28, in operation 2010, a current image is divided into at least one maximum encoding unit. In operation 2020, an encoded depth for sending a final encoding result according to at least one division region, which is obtained by dividing a region from each of the at least one maximum encoding unit according to depths, is determined by encoding of at least a division region and an encoding unit according to a tree structure is determined.

[000262] In operation 2030, a result of encoding image data according to an encoded depth for each of the at least one maximum encoding unit and an encoding result of information regarding the encoded depth and an encoding mode are sent.

[000263] Encoding unit pattern information corresponding to an encoded depth, which indicates whether texture information of encoding units according to encoded depths of at least one maximum encoding unit has been encoded, can be encoded as pattern information of encoding unit of at least one maximum encoding unit. If hierarchical encoding unit pattern information is hierarchically encoded according to a transformation depth, then each of a plurality of hierarchical encoding unit pattern information corresponding to transformation depths indicates whether the hierarchical encoding units relating to a transformation depth that is less than the corresponding transformation depth were encoded.

[000264] Fig. 29 is a flowchart illustrating a method for decoding video data using encoding unit pattern information according to an exemplary embodiment. Referring to Fig. 29, at operation 2110, an encoded video bit stream is received and analyzed.

[000265] In operation 2120, image data of a current image assigned to at least one maximum encoding unit, information regarding an encoded depth of an encoding unit according to a tree structure for each of the at least one maximum encoding unit and information about an encoding mode are extracted from the analyzed bit stream. Also, encoding unit pattern information indicating whether texture information for a maximum encoding unit has been encoded is extracted based on at least one maximum encoding unit. Encoding unit pattern information corresponding to an encoded depth regarding encoding units according to encoded depths of each maximum encoding unit and hierarchical encoding unit pattern information can be extracted as encoding unit pattern information from the at least one maximum encoding unit.

[000266] In operation 2130, encoded image data corresponding to at least one maximum encoding unit is decoded based on the encoded depths of the at least one maximum encoding unit, information about an encoding mode, and information about of the encoding unit pattern information, thereby reconstructing the image data. It is possible to determine whether texture information from the encoding unit corresponding to the encoded depth has been encoded based on the encoding unit pattern information corresponding to the encoded depth. In addition, it is possible to determine whether the hierarchical encoding unit pattern information about a lower transformation depth was encoded based on the hierarchical encoding unit pattern information about each of the transformation depths.

[000267] In the encoding unit corresponding to the encoded depth, data encoded in a transform unit can be decoded by performing an inverse transform to a transform coefficient based on transform unit pattern information from the transform unit.

[000268] In general, a video encoding/decoding method of the prior art, a 16 x 16 or 8 x 8 macroblock is used as a transform unit when transforming or inverse transforming is performed on image data. Encoded block pattern information is encoded and transmitted on a macroblock basis during an encoding process and is used for a decoding process.

[000269] In contrast, according to the above-described exemplary embodiments, encoding unit pattern information based on a hierarchically structured encoding unit and transformation unit is used. Thus, encoding unit pattern information can be encoded in an encoding unit that is larger than a macroblock or is a data unit of varying size. Furthermore, the encoding unit pattern information may be encoded in an encoding unit which includes a plurality of hierarchical structured transform units according to a tree structure in an integrated manner. Thus, the efficiency of encoding/decoding and transmitting the encoding unit pattern information can be improved.

[000270] One or more exemplary modalities may be incorporated as a computer program. The computer program may be stored on a computer readable recording medium and executed using a general digital computer. Examples of computer readable media include a magnetic recording medium (a ROM, a floppy disk, a hard disk, etc.) and an optical recording medium (a CD-ROM, a DVD, etc.).

[000271] While exemplary embodiments have been particularly shown and described, it will be understood by those skilled in the art that various changes may be made to the form and details thereof without departing from the spirit and scope of the present inventive concept as defined by the appended claims. Exemplary modalities are to be considered in a descriptive sense only and not for purposes of limitation. Therefore, the scope of the present inventive concept is defined not by the detailed description of exemplary embodiments, but by the appended claims, and all differences within the scope will be interpreted as being included in the present inventive concept.

Claims (1)

1. APPARATUS FOR DECODING VIDEO, characterized in that it comprises: an extractor that extracts from a stream of bits, encoded image data from a current image assigned to a maximum encoding unit of the current image, extracting, from the bit stream, information about an encoded depth to the maximum encoding unit, wherein the encoded depth information comprises information divided from a current encoding unit, the maximum encoding unit being hierarchically divided into encoding units of at least one depth according to the divided information which is a flag indicating whether the current encoding unit of a current depth, among the encoding units, is divided into encoding units of a smaller depth, and when the encoding unit division information current to indicate that the current encoding unit of the current depth is no longer split as the unit current encoding ade of the encoded depth, extract, from the bit stream, information about a prediction mode of the current encoding unit indicating an intra mode or inter mode, information about a partition type indicating a size of an included prediction unit in the current encoding unit and information about a size of one transform unit of the current encoding unit; and a decoder that determines at least one prediction unit obtained from the current encoding unit using information about a partition type and determines at least one transformation unit obtained from the current encoding unit using information about a size of a transformation unit, and performs intra-prediction or inter-prediction on the current encoding unit based on at least one prediction unit using information about a prediction mode, wherein the extractor extracts from the bit stream information from the encoding unit pattern which indicates whether the texture information of the current encoding unit has been encoded, according to whether the pattern information of encoding unit indicates that the texture information of the current encoding unit has been encoded, the extractor extracts, from the bit stream, transform unit pattern information indicating whether the texture information of at least one transform unit of the tr The information has been encoded, according to whether the transform unit pattern information indicates that the transform unit texture information has been encoded, the decoder performs an inverse transform on the transform unit and decodes the encoded image data to the transform unit. maximum encoding based on the prediction unit and the transform unit included in the current encoding unit, where the maximum encoding unit has a square shape with width and height in powers of 2.

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